In an experiment investigating the impact of a novel mindfulness meditation technique on the stress levels (measured via salivary cortisol) of air traffic controllers during peak hours, the researchers used an independent groups design. Consequently, individual differences in baseline stress tolerance (participant variables) could have acted as a confounding variable, compromising the internal validity of the study.
Outline one way in which the researchers could have addressed this issue.
Practise AQA A Level Psychology Scientific processes with exam-style questions for A Level Psychology. 689 questions, matched to the AQA A Level Psychology (7182) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
